Satellite-based communications systems are well are represented in the prior art. By example, reference is made to U.S. Pat. No. 5,303,286, issued on Apr. 12, 1994 to Robert A. Wiedeman, and which is entitled "Wireless Telephone/Satellite Roaming System". Reference is also made to the numerous U.S. Patents, foreign patents, and other publications that are of record in U.S. Pat. No. 5,303,286.
Of particular interest herein is a class of satellite-based communication systems that employs multiple satellites in a low earth orbit, referred to as a `LEO` system or LEOS. LEOS are characterized by moving patterns of signal `footprints` on the ground, where each footprint corresponds to the coverage area of one or more beams that are transmitted and received by a given satellite as it orbits the earth. The satellites communicate with terrestrial stations which may be referred to as gateways. The satellites may serve as repeaters for relaying a communication, such as a telephone call, from one ground station to another. One of the ground stations may be a gateway while another may be a user having a hand-held or vehicle mounted transceiver.
Other types of satellite-based communication systems exist or have been proposed wherein individual satellites are capable of relaying a communication directly to another satellite, without requiring an intermediate ground station. However, this added functionality comes at the cost of increased satellite complexity.
Reference can be had to U.S. Pat. No. 5,008,952 (Apr. 16, 1991), entitled "Global Satellite Communication System with Geographic Protocol Conversion", by Davis et al. In accordance with the teaching of this U.S. Patent a satellite paging system employs cross-linked non-synchronous satellites that include a programmable encoder for encoding, into a second data format, received data packets that are encoded in a first data format. The second data format is intended to correspond to the signalling requirements of portable communication receivers in a particular geographical delivery area.
As may be realized, this approach requires an increase in complexity of each satellite, as the satellite must perform on-board signal processing of the received transmissions for routing the received transmissions and for performing the data packet encoding function.